改扩建路堑段边坡稳定性评价及拓宽方式研究

发布时间：2019-03-03 08:19

【摘要】：改扩建工程中，连续高边坡路段开挖施工难度大、工期长，对道路运营影响大且需临时封道。因此，本文依托杭州（红垦）至金华高速公路改扩建项目，结合现场调查资料、理论分析和理正岩土软件计算等方法，对扩建过程中连续高边坡路段的边坡稳定性和拓宽方式展开研究，主要研究成果如下：（1）对杭州（红垦）至金华高速公路沿线边坡的区域环境进行了调查分析，初步掌握了老路边坡的分布情况及其稳定性，分析了边坡的变形破坏机理。（2）结合调查资料和理正岩土软件，计算分析了不同因素影响下边坡的稳定性变化规律，结果表明，边坡安全系数随着岩体中裂隙水的水位上升而减小；单级开挖深度对边坡安全系数的影响不及坡率的大；岩层倾角与边坡稳定性之间并不是简单的递增或递减关系。（3）对K92~K96路段的一处五级高边坡扩建过程中的稳定性进行分析，，并分析锚杆设计对边坡稳定的影响，从而优化加固方案，结果表明，当采用自上而下的开挖方式时，对第四级边坡开挖后，边坡安全系数较上一级有所增加；随后安全系数随着开挖与支护工序的变化而上下波动，但由于施工扰动的影响，整体呈下降趋势；越靠近坡脚的边坡开挖对边坡整体稳定性影响越大；随着锚杆长度的增加，边坡安全系数的增幅慢慢减小；安全系数随着锚杆锚固角的增大而增大，当增大到一定程度后，安全系数反而减小；上短下长的锚杆布置方案更有利于边坡整体稳定性。（4）遵循改扩建的基本原则，并结合边坡稳定性评价结果，对K92~K96连续高边坡路段的两种不同拓宽方案进行比较分析，最终认为单侧拼宽方案更经济合理。
[Abstract]:In the reconstruction and expansion project, the excavation construction of the continuous high slope section is difficult and the construction period is long, which has a great influence on the road operation and requires temporary closure of the road. Therefore, this paper relies on Hangzhou (Red Reclamation) to Jinhua Expressway reconstruction and expansion project, combined with field investigation data, theoretical analysis and straightening geotechnical software calculation methods, etc. The main research results are as follows: (1) the regional environment of slope along Hangzhou (Hongken)-Jinhua Expressway is investigated and analyzed. The distribution and stability of the old road slope are preliminarily grasped, and the deformation and failure mechanism of the slope is analyzed. (2) based on the investigation data and the software of straightening rock and soil, the stability of the lower slope is calculated and analyzed. The results show that the safety factor of the slope decreases with the water level of the fissure water in the rock mass rising; The influence of single-stage excavation depth on slope safety factor is not as large as that of slope rate, and the relationship between rock slope inclination and slope stability is not a simple increasing or decreasing relationship. (3) the stability of a fifth-grade high slope in K92~K96 section is analyzed, and the influence of bolt design on slope stability is analyzed, so as to optimize the reinforcement scheme. The results show that when the top-down excavation method is adopted, After excavation of the fourth grade slope, the safety factor of the slope is higher than that of the upper grade. Then the safety factor fluctuates with the change of excavation and support process, but because of the influence of construction disturbance, the overall trend decreases, and the slope excavation closer to the foot of the slope has a greater impact on the overall stability of the slope. With the increase of bolt length, the increase of slope safety factor decreases slowly, and the safety factor increases with the increase of anchor angle, but decreases when the anchor angle increases to a certain extent. The layout scheme of the upper and lower length bolt is more favorable to the overall stability of the slope. (4) following the basic principle of reconstruction and expansion, and combining with the evaluation results of slope stability, this paper makes a comparative analysis of two different widening schemes of K92~K96 continuous high slope section, and finally considers that the one-sided widening scheme is more economical and reasonable.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U416.1

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